Tyche in Hesiod and the Homeric Hymn to Demeter is an Oceanid daughter of Oceanus and Tethys — named among the eldest daughters in the Theogony and among Kore's playmates in the hymn (as Pausanias stresses when he says Homer first named Fortune as Ocean's child). The atlas node tyche-oceanid is that catalogue nymph, kept strictly distinct from the later civic and Hellenistic goddess of city-fortune (mural crown, cornucopia, Fortuna) who inherited the name.
Adapted from Wikipedia, "Tyche" · CC BY-SA 4.0
I.Oceanid in the poets
Hesiod closes a run of eldest Oceanids with Tyche beside Telesto, Chryseis, Asia, Calypso, and Eudora before Amphirho, Ocyrrhoe, and Styx. No Theogonic myth attaches beyond that genealogical honour.
Pausanias argues that Homer was first to name Fortune in verse, citing the Homeric Hymn to Demeter: among the daughters of Ocean playing with Kore in the meadow stand Leucippe, Phaeno, Electra, Ianthe, Melobosis, Tyche, and Ocyrhoe. Here Fortune is an Oceanid playmate of Persephone, not yet the city-protectress of later cult.
II.Distinct from civic Tyche
Classical and Hellenistic literature also know Tyche as tutelary fortune of cities and of capricious fate — daughter variously of Oceanus and Tethys, or of Zeus, or of Prometheus; mother sometimes of Plutus; worshiped with mural crown and cornucopia from Itanos and Athens to Alexandria and Antioch, and equated with Roman Fortuna. Polybius and Pindar already treat her as the cause of inexplicable reverses and athletic outcomes.
That civic and philosophical Tyche eclipsed the catalogue nymph in later imagination. This reference file documents the shared Wikipedia article while the atlas character tyche-oceanid remains the Hesiodic / hymnic Oceanid only — not Automatia, not Nemesis-Tyche, not the Tychai of Rome and Constantinople.